Steve Irwin: 1962-2006

"He was so genuinely passionate," says friend Jon Dee of Irwin (left) in 2003 in one of his many "Crikey!" moments from Crocodile Hunter.

GREG BARRETT/BEST PICTURE SHOW COMPANY

09/07/2006 AT 12:00 PM EDT

He was supposed to be shooting scenes along Australia's Great Barrier Reef for a documentary he was making called Ocean's Deadliest, but the waters there were too cloudy. Never one to fritter away an idle moment, the ever-energetic adventurer and Crocodile Hunter Steve Irwin decided to film a segment for his daughter Bindi's upcoming wildlife show on the Discovery Kids channel.

In fact, he was kind of looking forward to it. "He was in such a good frame of mind," says his longtime friend and producing partner John Stainton, who was with him Sept. 4 on the deck of Irwin's 75-ft. research boat Croc One. "We sat together in the early hours, 5 a.m., 6 a.m., having a cup of tea, just talking about how good life was."

Anchored at Batt Reef off the resort town of Port Douglas in Queensland, Irwin, 44, slipped into the water with his cameraman to film a school of stingrays. For a man who had tussled with crocs, venomous snakes and other frightening creatures, this was going to be a leisurely swim. Better than most anyone, he knew that stingrays are so docile that they generally put up with the prying eyes and underwater cameras of amateur divers. Then it happened.

As he was snorkeling in waters no more than 10 feet deep, he passed above a bull ray, which can grow up to seven feet in diameter. For some reason it stopped, then suddenly whipped its razor-sharp tail directly up toward Irwin and plunged the barb deep into his chest, piercing the heart.